If this were viable, why would it not have worked before?

Because something wasn't in place to make it work. There are millions of examples where the second mover won, often because the first mover was too early, or the tech wasn't there to make it work, or the market didn't understand the value, etc.

In this case I imagine there are three massive benefits that you'd have over being the first mover:

- AWS is more mature and therefore moving slower, so it's easier to keep up.

- AI is useful for building 80% working code, so there's a lot less to do to keep up.

- There's a lot of devs looking for ways to move off Localstack due to the price change, which gives you (potentially) a pool of willing volunteers to contribute to an OSS alternative.

You can also learn from Localstack's open source version about what's needed, what works, what doesn't work, etc.